INTRODUCTION. • 7
not try to do it, but called everything that was made in the Bessemer converter, or in the open-hearth furnace, or in the crucible, by the name "steel."
A few scientific committees tried to make new names, but their labors came to naught in England and America. In Germany the committees had their way for many years, and the soft rnetals of the converter and the open-hearth were called ingot-iron. This term still survives in metallurgical literature, but in the German works where the metal is made, it is called steel, and the plant itself is called a stalil wer'ke (steel works), so that we have the peculiar anomaly of a steel works making what is called steel by the workmen, while the official reports declare that it makes no steel at all. It seems inevitable that Germany must soon give up this outgrown system.
The current usage in our country and in England in regard to wrought-iron and steel may be summarized in the following definitions :
(1) By the term wrought-iron is meant the product of the puddling furnace or the sinking fire.
(2) By the term steel is meant the product of the cementation process, or the malleable compounds of iron made in the crucible, the converter or the open-hearth furnace.
THE MAKING 'OF CRUCIBLE STEEL.
Most of the hard steel in the market to-day is made in the open-hearth furnace. Enormous quantities are used for car springs and agricultural machinery, and both the acid and basic furnaces furnish a share. There are some purposes, however, which call for a steel entirely free from the minute imperfections often present in open-hearth metal. Such is the case in watch-springs, needles and razors; and it is found that the old crucible process gives in the long run the most satisfactory metal for such work.
This process consists in putting into a crucible a proper mixture of scrap, pig-iron, or charcoal and heating it until everything is thoroughly melted, the crucible being kept tightly closed to prevent the admittance of air. This process is a century old, but bids fair to round out another with little change.
THE ACID BESSEMEE PEOCESS. The Bessemer process consists in blowing cold air through liquid